Psychology
2013. Vol.4, No.7A, 1-10
Published Online July 2013 in SciRes (http://www.scirp.org/journal/psych) http://dx.doi.org/10.4236/psych.2013.47A001
Bilingualism and Measures of Spontaneous and Reactive
Cognitive Flexibility
Raphiq Ibrahim1,2*, Reut Shoshani1, Anat Prior1,2, David Share1,2
1Learning Disabilities Department, University of Haifa, Haifa, Israel
2The Edmond J. Safra Brain Research Center for the Study of Learning Disabilities,
University of Haifa, Haifa, Israel
Received April 20th, 2013; revised May 22nd, 2013; accepted June 21st, 2013
Copyright © 2013 Raphiq Ibrahim et al. This is an open access article distributed under the Creative Commons
Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the
original work is properly cited.
In this study, we assessed possible consequences of bilingualism on executive function among adults.
Three groups of adults were tested with a series of tests designed to tap two types of cognitive flexibility:
reactive flexibility and spontaneous flexibility (The experimental groups comprised bilinguals equally
proficient in Hebrew and English (balanced), Hebrew-dominant bilinguals and English-dominant bilin-
gual participants). The results revealed several significant differences where the balanced bilinguals per-
formed better relative to individuals from the same cultural background. In both types of flexibility tasks,
the balanced-bilinguals were found to be superior to the Hebrew-dominant group but not compared to
those who mastered English as their primary language. A significant difference between the balanced-bi-
lingual group and the Hebrew-dominant group was found in the task which required spontaneous cogni-
tive flexibility and the one which required reactive cognitive flexibility. The comparison of these unique
findings with other findings in the literature and their psycholinguistic implications are discussed.
Keywords: Bilingualism; Attention; Executive Functions; Spontaneous Flexibility; Reactive Flexibility
Introduction
In everyday life, the bilingual person has to be sensitive to
external linguistic signals from his or her surroundings (“bot-
tom-up” control) and at the same time must perform an internal
directing (“top-down” control) in order to translate the external
input and choose the language in which s/he wants to produce
the output (Green, 1998). These choices are considered to en-
hance executive aspects of perception and thinking for children
(Bialystok, 1999; Carlson & Meltzoff, 2008) and adults (Col-
zato, Bajo, van den Wildenberg, Paolieri, Nieuwenhuis, La Heij,
& Hommel, 2008). Several studies have shown that among
bilinguals both languages are active even if only one of them is
being used (Brysbaert, 1998). It was found, for example, that
bilingual subjects can listen to one language while simultane-
ously speaking in their second language (Grosjean, 1988). The
joint brain activity of the two languages requires a mechanism
for keeping the languages separate in order to allow fluent
speech in one language without any intrusions from the other
one. Green (1998) developed an inhibitory control model in
which the non-relevant language is suppressed by the same
executive functions used generally to control attention and in-
hibition. Another study used a modified antisaccade task in
order to explore the cognitive effects of bilingualism among
adults (Bialystok, Craik, & Ryan, 2006). In a typical antisac-
cade task, the viewer fixates a central location while a stimulus
is flashed to one side of the fixation. The viewer is asked to
make an antisaccadic eye movement in the opposite direction to
the flashed cue. Success on this task requires the ability to
override the reflexive response of initiating a saccade toward a
target and is therefore is tied to intact executive functions. An
advantage was found among bilingual adult subjects in a ver-
sion of the task which used a behavioral response method.
The advantage was seen under different task conditions rep-
resenting distinctive executive functions-response suppression,
inhibitory control and task switching. These executive proc-
esses are highly developed among bilinguals who must manage
and control two lexical systems.
Colzato and her colleagues (2008) explored the mechanism
underlying the bilingual advantage in inhibiting irrelevant in-
formation and representations. Their results suggest that the
cognitive processing advantages that bilinguals enjoy are not
due to direct active inhibition processing but rather to con-
structing and maintaining more efficient goal representations in
working memory. They propose that learning to keep two or
more languages separate leads to a general improvement in
“reactive inhibition” mechanisms in which goal-relevant infor-
mation is selected from competing goal-irrelevant information.
These results converge with other findings which suggest a bi-
lingual advantage in situations involving high processing de-
mands from working memory besides the executive need for
inhibition (Bialystok, Craik, Klein, & Viswanathan, 2004).
In most studies into the effects of bilingualism on executive
functions, as well as on other functions, children have been the
subjects. Children who grow up in a bilingual environment are
continually obliged to attend to the abstract dimensions of lan-
guage. Since they are able to name the same object with differ-
*Corresponding author.

R. IBRAHIM ET AL.
ent names, they come to appreciate the distinction between
words and their meaning, as well as understand the arbitrary
nature of object names (Ianco-Worrall, 1972).
Apparently, bilingual children are said to acquire an advan-
tage in a process defined by Bialystok (1993) as the “analysis
of representations”—the process by which mental representa-
tions are constructed in memory, and the way in which they are
organized, analyzed and retrieved. The need to associate words
from two languages with a common concept requires more ad-
vanced representation because the connections between the words
exist at a more abstract level than the connection between a
particular word and its meaning. This semantic structure might
be expected to be more hierarchical than that of the monolin-
gual, and the process of constructing this structure could en-
hance children’s representational processes (Bialystok, 1999).
Previous research conducted by Bialystok (1999) has dem-
onstrated that bilingual children showed an advantage over
monolingual children on the Wisconsin Card Sorting Task
(WCST) which involved switching from one set of rules to
another. Later, Zied and his colleagues supported this conclu-
sion by using a Stroop Task where the subjects were required to
respond to the ink color in which color names are printed while
ignoring the color word itself (Zied, Phillipe, Karine, Valerie,
Ghislaine, & Arnaud, 2004). They explained that the need to
manage two lexical systems created a considerable cognitive
challenge for the bilingual person. In addition to the need to
maintain separate access to each language, there are situations
in which concurrent use of the two languages takes place ne-
cessitating a selection between two competitive responses. Re-
cent research on bilingual aduls suggested that a bilingual’s
experience with language switching speeded the maturation of
attention and executive processes (Kiesel et al., 2010; Meiran,
2010). The question of whether the specific language combina-
tions that bilinguals speak might influence the existence or
degree of cognitive benefits they enjoy has only recently started
to receive attention in the literature ((Bialystok, 2010; Costa,
Hernandez, & Sebastian-Gall’s, 2009; Hilchey & Klein, 2011;
Prior & MacWhinney, 2010; Prior & Gollan, 2011). Hilchey
and Klein (2011) similarly locate the bilingual advantage in a
central executive system that regulates processing across a wide
range of tasks and domains. They explained that the bilingual
advantage is mainly attributed to the need to manage language
selection. The continual use of and exposure to two languages
throughout life promotes executive functioning, as mentioned
before, and therefore may increase the effectiveness of the cor-
tical region responsible for these functions. Evidence that
switching languages is supported by the same neural paths
which are responsible for other cognitive control mechanisms
comes from an ERP study which compared brain activity dur-
ing language switching in a digit naming task to activity during
suppression of responses in a Go/No-Go task among bilingual
subjects (Jackson, Swainson, Cunnington, & Jackson, 2001).
Another imaging study which supports the assumption that the
management of two language systems leads to systematic
changes in frontal executive functions was carried out by Bia-
lystok, Craik et al., (2005). In this study, young bilingual sub-
jects activated more frontal regions compared to monolingual
subjects during a task which required inhibition control.
Bilingualism has also been shown to have a positive effect
on the functioning of an individual’s attentional system across
the life-span (e.g., Bialystok, 1999; Costa et al., 2008). Using
the Flanker Task (subjects are asked to indicate whether a cen-
tral arrow that was presented along with four flanker arrows
pointing to the same [congruent] or different [incongruent]
direction points to the right or to the left), Costa and his col-
leagues (2008) showed that responses tended to be slower for
incongruent than for congruent trials (the conflict effect). The
bilingual advantage in this task was indexed by a reduced con-
flict effect for bilinguals in comparison to monolinguals. The
researchers claimed that, this effect may reflect an impact of
bilingualism on the efficiency of other cognitive processes than
conflict resolution per se, as has already been suggested by
several authors (e.g., response suppression and switching; Bia-
lystok, Craik, & Ryan, 2006).
In a recent study, Prior and colleagues (Prior & Gollan, 2011;
Prior & MacWhinney, 2010), tried to elaborate on the nature of
executive control advantages accrued by bilinguals, with spe-
cific emphasis on cognitive flexibility; and how individual dif-
ferences in executive control and cognitive flexibility might
further our understanding of the variability in second language
learning outcomes.
They compared the performance of bilinguals and monolin-
guals in a task switching paradigm that included only two tasks,
and most importantly, task repetition trials. The inclusion of
task repetition trials allows for calculating switching costs,
namely, the increased difficulty in responding in trials where
the task set changes when compared to trials where the task set
remains unchanged. In this paradigm, bilinguals demonstrated a
smaller switch cost than monolinguals, although in Prior and
Gollan (2011) this finding was limited to only one of the two
bilingual groups examined.
According to Bialystok (1993), because bilinguals hold lin-
guistic representations of two languages, they consistently ex-
perience the need to attend to representations from one lan-
guage while inhibiting these from the irrelevant language. This
dissociation between “analysis of representations” and “control
of attention” has been found in tasks from several domains. In
meta-linguistic tasks, bilingual children have been found to be
superior to monolinguals at judging the grammaticality of sen-
tences containing distracting semantic information (for example,
deciding whether the sentence Apples grow on noses is gram-
matically correct), but both groups were equivalent in detecting
grammatical violations in sentences that had no distracting
information (Apples on trees grow) (Cromdal, 1999).
The Present Study
The above literature highlights the contribution of bilingual-
ism to the development of executive functions, starting from
early childhood. As noted earlier, previous studies among adult
bilinguals have focused on executive functions which involve
selective attention and control of inhibition as well as on work-
ing memory. The present study will expand the frame of refer-
ence to the executive function of cognitive flexibility which has
not been examined to date. However, it should be mentioned
that a previous study (Bialystok, Martin & Viswanathan, 2005)
examining the executive functions of control of attention and
inhibition with the “Simon Task1”, unexpectedly found a bilin-
1The Simon task assesses the extent to which subjects respond when stimu-
lus and response side corresponded compared to when they did not, even
when stimulus positions were irrelevant for the task. For example, if sub-
j
ects are asked to press a left key in response to a green stimulus and a right
key in response to a red stimulus, response will be faster when the green
stimulus ap
p
ears on the left than when it appears on the right. The influence
of the irrelevant spatial stimulus feature on performance is known as the
Simon effect (see review in Lu & Proctor, 1995).
2

R. IBRAHIM ET AL.
gual advantage in both task conditions (congruent and incon-
gruent) across a wide range of ages. It might be that these re-
sults indicate bilingual superiority in managing a mixed set of
items - a process which requires cognitive flexibility.
According to Spiro and Jehng (1990), cognitive flexibility is
defined as “the ability to adaptively re-assemble diverse ele-
ments of knowledge to fit the particular needs of a given under-
standing or problem-solving situation” (p. 169). According to
Eslinger and Grattan (1993), cognitive flexibility is not a uni-
tary process, and is based on multiple components such as pro-
duction of a diversity of ideas, considering response alterna-
tives and modifying plans and behavior in response to changing
circumstances in order to attain long term goals.
From a neurocognitive point of view, cognitive flexibility
has been localized to the frontal lobes (Cicerone, Lazar, &
Shapiro, 1983; Milner & Petrides, 1984). Eslinger & Grattan
(1993) distinguished between two types of cognitive flexibility:
Spontaneous flexibility and reactive flexibility. Spontaneous
flexibility refers to the ability to generate a diversity of ideas.
Spontaneous flexibility tasks typically require subjects to ac-
cess various classes and categories of knowledge while by-
passing automatic and habitual responses and strategies in order
to attend to novel features of knowledge. In contrast, reactive
flexibility refers to the readiness to shift cognition and behavior
according to the particular demands and context of a situation.
It is important to emphasize that bilingualism is not an
“all-or-none” phenomenon but is rather an individual charac-
teristic which can exist in different degrees (Hornby, 1977).
Indeed, it is possible to define groups of bilinguals according to
their relative proficiency in each of two languages. Lambert,
Havelka and Gardener (1959) introduced the term “balanced
bilingualism” to refer to individuals with full linguistic compe-
tence in both languages. On the other hand, a “dominant” bi-
lingual person has higher proficiency in one language, and uses
it more often than the other language (Wei, 2000).
Due to expanding globalization processes in recent decades,
it has become increasingly difficult to identify individuals who
have been exposed to only a single language throughout their
lives (monolinguals). Therefore, the present study explored the
effect of bilingualism on the executive function of cognitive
flexibility by comparing a group of balanced bilinguals who
have “mother tongue” proficiency in two languages, to two
other dominant bilingual groups.
Since studies with bilingual adults (Kroll & Stewart, 1994)
and children (Bialystok, 1999) have revealed that the cognitive
and linguistic consequences of bilingualism are more salient for
those bilinguals who are relatively balanced in their proficiency,
the main hypothesis of the present study is that balanced bilin-
gual subjects would perform better on various cognitive tasks
compared to dominant bilingual subjects. In addition, due to the
fact that spontaneous cognitive flexibility requires more cogni-
tive resources and more advanced executive abilities, the sec-
ond hypothesis of the present study is that the the balanced
bilinguals’ performance would be stronger in cognitive tasks
which require spontaneous cognitive flexibility.
Method
Subjects
Forty-nine right-handed young adults ranging in age from 20
to 35 years (M = 24.4, SD = 3.5) participated in this study.
There were no significant differences between the mean ages of
the three groups and none of the subjects in this study reported
having either attention deficits or learning disabilities. There
were three bilingual groups in this study: Balanced bilinguals (n
= 17).
Hebrew-dominant bilinguals (n = 17) and English-dominant
bilinguals (n = 15). The criterion for being designated a bal-
anced bilingual was that both English and Hebrew were used
actively on a daily basis since early childhood. Most of the
balanced bilingual subjects had grown up in “mixed” families
where one of the parents spoke English as a native language
and the other spoke native Hebrew. Some subjects came from
homes (in Israel) in which both parents spoke English, and
were therefore exposed to both languages since infancy. In
addition, some of the subjects in this group resided for varying
periods in an English-speaking country.
Subjects in the Hebrew-dominant group were young Israeli
adults who speak Hebrew as a native language and were not
functionally fluent in any other language. The subjects in the
English-dominant group were foreign students who came to
Israel for academic studies. English was their native tongue and
they were not fluent in any other language.
Tools and Procedure
Language Background Questionnaire
All subjects completed a language background questionnaire
to establish their language history and patterns of language use.
For each language known to the subject, three dimensions of
language fluency (spoken production, reading and writing)
were rated on a 6-point scale ranging from not fluent at all (0)
to extremely fluent (5). Subjects in the balanced-bilingual group
rated themselves as being highly fluent both in Hebrew (aver-
age of the three language dimensions: M = 4.98, SD = 0.35) and
in English (average of the three language dimensions: M = 4.73,
SD = 0.26) while subjects in the other two groups rated them-
selves as being highly fluent only in one language. Although
the data reveal higher self-reported second language profi-
ciency of the Hebrew-dominant group (M = 3.3) than the Eng-
lish-dominant group (M = 1.9), the background data reported by
the subjects reinforces the distinction between the balanced-
bilingual group who were exposed to two languages from early
childhood and the other two groups who reported acquiring the
second language later in life without using it on a daily basis. It
is possible that cultural factors partly explain the differences in
self-evaluations, that is, an over-estimation of the Hebrew-do-
minant group’s English skills.
In order to ensure that the balanced bilingual group had met
the research criteria of speaking Hebrew and English since
early childhood, the subjects in this group completed an addi-
tional language questionnaire. In this questionnaire, they were
asked to indicate the percentage of time in which each language
had been used during three periods of their life: language usage
at home, at school (or university) and with friends. The bal-
anced-bilingual group reported using Hebrew 52.8% of the time
up to the age of 12 years. Between 12 to 18 years they reported
using Hebrew 61.7% of the time and 59.3% in their adulthood.
These findings are displayed in Table 1.
1) Background measures
In order to partial out the influence of verbal and non-verbal
general intelligence as well as memory capacity, the following
tasks were administrated:
Raven’s Standard Progressive Matrices (Raven, 1958). This

R. IBRAHIM ET AL.
4
Table 1.
Mean percentage of time usage (means and standard deviations in parentheses) of Hebrew across the life-span among balanced bilinguals.
Home School/University Friends
M (SD) M (SD) M (SD)
Overall M (SD)
Up to 12 years old 24.1 (23.8) 72.4 (33.1) 62.1 (30.2) 52.8 (25.4)
Between 12 - 18 years old 24.1 (23.73) 86.8 (16.58) 74.1 (23.4) 61.7 (33.12)
Above 18 years old 27.1 (24.94) 78.4 (27) 72.4 (22.78) 59.3 (28.07)
Note: Mean percentage of English-language time usage is the reciprocal of these figures.
standardized test was originally designed as a measure of non-
verbal reasoning ability. The test contains five sets, each of 12
items (A to E). In each test item, the subject is asked to identify
the missing segment required to complete a larger pattern. All
items are presented in black ink on a white background. Both
the sets and the items within each set are arranged in order of
difficulty. Subjects are given a score for each correct answer,
and a general summary score is also calculated.
Vocabulary (Wechsler, 1981). The vocabulary subtest from
the Wechsler Adult Intelligence Scale-Revised (WAIS-R) was
administered in order to assess general verbal intelligence. This
test consists of 33 words (the Hebrew version) or 35 words (the
English version) which the subject has to define. The English
version of the test was administered to the English-dominant
bilingual group, while the Hebrew version was administered to
both the Hebrew-dominant bilingual group and the balanced
bilingual group. Depending on the definition given by the sub-
ject, each response was awarded up to two points. The general
raw score was converted into a standardized score based on
subjects’ age.
Digit Span (forward and backward). This task was used as a
measure of verbal memory capacity. It has two parts (digit span
forward and digit span backwards)—each composed of a series
of digit strings. Subjects were required to repeat each string of
digits after it had been spoken by the experimenter—in the
same order (digit span forward) or in reverse order (digit span
backwards). There are two trials at each string length (ranging
from two to nine). Each part of the task was discontinued when
two consecutive errors at the same string length were made.
The overall score in each part was the total number of correct
digit series reproduced by the subject. An average score for
performance on both parts was calculated.
Wechsler Memory Scale III Spatial Span (forward and
backward). This task, a measure of visual-spatial memory span,
contains two parts (spatial span forward and spatial span back-
wards). Ten cubes are attached to a board in an irregular ar-
rangement. In each trial, the experimenter taps the blocks in a
prearranged sequence (which varies from a sequence of two to
eight cubes). The subject is required to reproduce the tapping
pattern as it was presented (spatial span forward) or in the re-
verse order (spatial span backwards). Each part of the task was
discontinued when two consecutive errors at the same sequence
length were made. The overall score for each part was the
number of correct sequences tapped by the subject. An average
score for performance on both parts was also calculated.
2) Experimental measures
a)Spontaneous cognitive flexibility
In order to assess spontaneous cognitive flexibility, the fol-
lowing tasks were administered:
Alternate Uses (adapted from: Guilford, Christensen, Merri-
field & Wilson, 1978). In the “Alternate Uses” Task each sub-
ject is asked to think beyond the common or conventional use
of six objects, and to think up as many alternate uses as come to
mind during 80 seconds for each object. The objects were—a
bed sheet, a paper clip, a shoe, a cardboard box, an automobile
tire and a drinking glass. Acceptable responses were conceiv-
able uses that were different from each other and different from
the common use. The overall score was the number of accept-
able responses for all six objects.
Design Fluency (Jones-Gotman & Milner, 1977). The Design
Fluency Task was administered according to procedures de-
veloped by Jones-Gotman and Milner (1977). Each subject was
given four minutes in which to come up with as many different
kinds of drawings as s/he could, using four lines, straight or
curved, each time. The subject was instructed not to draw
meaningful forms (such as the letter “W” or a square) and was
shown examples of acceptable and unacceptable drawings. All
repetitions were identified and subtracted from the total: these
included rotations or mirror-image versions of previous draw-
ings. In addition, all nameable drawings or drawings with an
incorrect number of lines were also disqualified. The overall
score was the number of remaining drawings.
b) Reactive cognitive flexibility
In order to assess reactive flexibility, two other tasks were
also administered:
WCST (Wisconsin Card Sort Task) (Heaton, Chelune, Talley,
Kay, & Curtis, 1993): Each subject was given a set of 128 cards
on which were printed up to four identical figures of either stars,
crosses, triangles, or circles in one of four different colors.
These figures were the basis for three sorting principles: color,
form and number. At the beginning of the task, four stimulus
key-cards were placed before the subject (one red triangle, two
green stars, three yellow crosses and four blue circles). The
instruction was to place each of the consecutive response cards
in front of one of the stimulus cards, wherever it appears to
match best. The subject is not informed of the correct sorting
principle but was required to deduce this from the examiner’s
responses to his or her placements of the cards (“right” or
“wrong” feedback statements). After 10 consecutive correct
sorts, the examiner shifted the to-be sorted principle without
warning. This procedure continued until either five shifts of
sorting category had been completed, or all cards were sorted.
The ability to flexibly change response sets in this task was
measured by three measures: the number of sorting steps re-
quired to complete the first category (WCSTFC), the number of
“total errors” (defined as the total number of incorrect sorting
steps, WCSTTE) and the number of perseverative responses
(defined as a sorting by the previous strategy after a correct

R. IBRAHIM ET AL.
sorting by a new strategy, WCSTPR). In all of these measures,
higher scores represent greater impairment (i.e. less cognitive
flexibility).
Trail Making Test (Reitan, 1979). The Trail Making Test
contains two sub-sections accompanied by short sample items
prior to the administration of each part. In part A, the subject is
presented with a page with the numbers 1 through 25 and is
required to draw a line connecting the numbers in order, as
quickly as possible. In part B, a page is presented with the
numbers 1 through 13 and the letters A through L (or the cor-
responding Hebrew letters in the Hebrew version of the task).
In this part, the individual’s task is to draw a line connecting
the numbers and letters in order, alternating between numbers
and letters (e.g. 1-A-2-B, etc.). Two scores were obtained, re-
flecting the total time in seconds to complete each part (Tr1,
Tr2 respectively). In this case, a lower figure indicates better
performance. According to the Reitan (1979) administration
format, errors are not scored, but when they occurred, the sub-
ject was alerted to the mistake and instructed to correct it, thus
slowing overall performance time. In order to create a score
which reflects the ability to alternate between two sets of stim-
uli (cognitive flexibility), another score was calculated by di-
viding the performance time of Trails B by the performance
time of Trails A (Tr2/Tr1). A higher score represents greater
difficulties in performing this task.
Results
Background Measures
Table 2 shows the means and standard deviations for the
background measures by subject group.
All subjects had normal scores on the vocabulary subtest of
the Wechsler Adult Intelligence Scale Revised (WAIS-R). A
series of one-way analyses of variance (ANOVA) were con-
ducted.
Since no significant gender effects were found, gender was
ignored in all these analyses. No significant differences were
found between the groups on the general raw scores of the Ra-
ven’s Matrices, Digit Span Forward, Digit Span Backward or
the combined (forward plus backward) measure. The Spatial
Span Test also included forward and backward subtests. Whereas
no significant differences were found between the groups on
the forward subtest, the backwards subtest revealed a signifi-
cant difference. Post-hoc Tukey comparisons revealed a just
significant difference (p = 0.049) between the Hebrew-domi-
nant group and English-dominant group. The combined means
of the two subtests indicated no significant group differences.
Experimental Measures
Table 3 displays means and standard deviations (in paren-
theses) on the experimental cognitive flexibility measures.
Since there were specific predictions regarding a balanced-
bilingual advantage over the other two groups on the cognitive
flexibility measures, a series of planned comparisons (t-tests)
were conducted. Results are shown in Table 4.
Spontaneous cognitive flexibility was examined by two dif-
ferent tests: Alternate Uses and Design Fluency. In the Alter-
nate Uses Task, t-tests revealed a significant difference between
the balanced-bilingual group and the Hebrew-dominant group.
The estimated effect size was 0.292.
No significant difference was found between the balanced-
bilingual group and the English-dominant group, or between
the Hebrew-dominant group and the English-dominant group.
An additional two-way analysis of variance (ANOVA) was
conducted due to a significant influence of gender in which
women had higher scores compared to men, F(3, 45) = 4.01, p
= 0.05. However, no interaction was found between gender and
group.
In the Design Fuency Task, no significant differences were
found between any of the three groups. Reactive cognitive
flexibility was examined with two other tests; the Trail Making
Test (TMT) and the Wisconsin Card Sorting Test (WCST).
Planned comparisons (t-tests) for the TMT were conducted for
the three measures. For Trails 1, no significant differences be-
tween groups were found. However, on Trails 2, the He-
brew-dominant group was found to be inferior (slower) than the
balanced-bilingual group and the English-dominant group-the
Table 2.
Means and standard deviations (in parentheses) on background cognitive measures in three groups.
Balanced bilinguals Hebrew dominant English dominant
M (SD) M (SD) M (SD) F P
Vocabulary 1.2 0.21
(WAIS-R) 15.9 (1.34) 16.1 (1.22) 14.3 (1.95)
Raven 52.2 (3.05) 50.1 (4.00) 50.1 (5.28) 1.4 0.26
Digit span forward 11.8 (1.92) 10.7 (1.49) 11.3 (1.88) 1.54 0.22
Digit span backward 7.9 (2.52) 8(2.15) 8.4 (1.55) 0.25 0.78
Digit span combined 9.8 (2.00) 9.4 (1.54) 9.9 (1.25) 0.5 0.61
Spatial span forward 8.6 (2.03) 8.5 (2.18) 8.7 (2.00) 0.04 0.96
Spatial span backward 8.8 (1.70) 7.4 (1.69) 8.9 (1.92) 3.83 0.03*
Spatial span combined 8.7 (1.48) 7.9 (1.56) 8.8 (1.71) 1.46 0.24
Note: *A Tukeypost-hoc comparisons revealed a significance difference (p = 0.049) between the Hebrew- dominant group and the English-dominant group.

R. IBRAHIM ET AL.
Table 3.
Means and standard deviations on experimental cognitive flexibility measures in three groups.
Balanced bilinguals Hebrew dominant English dominant
M (SD) M (SD) M (SD)
Spontaneous flexibility
Alternate
Uses 29.4 (5.7) 22.3 (5.6) 26.4 (6.48)
Design
Fluency 30.8 (10.25) 29.5 (12.86) 33.5 (11.05)
Reactive flexibility
Trails 1 29 (5.06) 31.7 (6.05) 28.3 (7.44)
Trails 2 52.8 (9.25) 61.1 (13.7) 51.4 (9.71)
Tr2/Tr1 1.9 (0.36) 1.96 (0.47) 1.9 (0.54)
WCSTFC 11.5 (2.35) 11.7 (2.5) 11.7 (2.4)
WCSTTE 9.1 (3.32) 9.6 (3.79) ^ 8.5 (2.33)
WCSTPR 5.7 (1.87) 6.4 (2.45) 5.8 (1.15)
Table 4.
Statistical comparisons between pairs of groups.
Balanced bilinguals vs. Hebrew dominantBalanced bilinguals vs. English dominantHebrew dominant vs. English dominant
t p Eta2 t p Eta2 t p Eta2
Alternate Uses 3.63 0.001* 0.292 1.37 0.18 −1.92 0.064
Design Fluenc y 0.32 0.75 −0.72 0.48 −0.94 0.36
Tr1 −1.4 0.165 0.31 0.76 1.43 0.16
Tr2 −2.01 0.047* 0.118 0.42 0.67 2.3 0.03* 0.148
Tr2/Tr1 −0.75 0.46 −0.35 0.73 0.29 0.77
latter two groups performed at similar levels. No significant
differences were found between the groups on the proportion
Tr2/Tr1.
For the WCST, an aparametric analysis (Mann-Whitney Test)
was conducted due to the abnormality of distribution. Results
are shown in Table 5.
As can be seen in Table 5, there were no significant differ-
ences between the groups on any of the three measures.
1) Spontaneous versus reactive flexibility
In order to explore the second hypothesis of the study, which
predicted that the balanced-bilingual superiority would be
greater in cognitive tasks which are assumed to tap spontaneous
cognitive flexibility, a repeated measures analysis of variance
(ANOVA) was conducted. Two composite measures of cogni-
tive flexibility (spontaneous and reactive) were created: The
spontaneous cognitive flexibility measure was an average of z
scores on the Alternate Uses Task and the Design Fluency Task.
In order to create the reactive cognitive flexibility composite,
we tried different combinations of experimental measures (for
example, combining z scores of the Trails 2 measure with z
scores of all WCST measures, or mean z scores of Trails 2 and
Trails 2/Trails 1 measures with all the WCST measures): the
same pattern of results emerged. Using a reactive cognitive
flexibility aggregate, which was a mean z scores of Trails 2,
Trails 2/Trails 1 and all WCST z scores, the following results
were obtained: No (pairwise) interactions were found between
group and type of cognitive flexibility when comparing the
balanced-bilingual group and the Hebrew-dominant group,
F(1,32) = 0.534, p = 0.47; between the balanced-bilingual
group and the English-dominant group, F (1,30) = 0.08, p =
0.78; and between the Hebrew-dominant group and the Eng-
lish-dominant group, F (1,30) = 0.22, p = 0.64.
The Alternate Uses Task is highly demanding from a cogni-
tive point of view.
It was found that subjects with greater executive capacity were
better able to succeed in this task and produce novel uses of
common objects (Gilhooly, Fioratou, Anthony, & Wynn, 2007).
In the present study a highly significant difference between
balanced-bilinguals and the Hebrew- dominant group was
found on this task. If the difference between the groups is sig-
nificantly greater than the difference between the groups in
other less demanding experimental measures (including the
6

R. IBRAHIM ET AL.
Design Fluency Task which also measures spontaneous cogni-
tive flexibility) then the assumption that bilingual experience
enhances cognitive function will be strengthened.
A series of repeated measures analyses of variance (ANOVA)
were conducted in order to explore this. Once again, standard-
ized scores were created for the purposes of these analyses.
Results are shown in Table 6.
Results indicated that the superiority of the balanced bilin-
gual group on the Alternate Uses Task (compared to the He-
brew-dominant group) was more pronounced than in most of
the Wisconsin measures (WCSTFC and WCSTTE) and in the
Design Fluency Task. The interaction was close to significant
with the combined measure of performance in the Trails Task
(Tr2/Tr1).
Discussion
Previous studies have indicated that bilingualism contributes
to the improvement of cognitive skills from childhood (Bialy-
stok, 1999) and adults (Colzato et al., 2008).
In the present study, an adult group of balanced bilinguals,
who are equally competent in English and Hebrew, was com-
pared to two different adult dominant-bilingual groups, each of
which had fully mastered only one language. All groups were
tested with a series of tests designed to tap two types of cogni-
tive flexibility: reactive flexibility (tested using the Trail Mak-
ing Test and the Wisconsin Card Sorting Test) and spontaneous
flexibility (tested using the Alternate Uses test and the Design
Fluency Task). The aim of the study was reach data that will
ultimately lead to a better understanding of the nature and vari-
ability of bilingual language and cognitive profiles. Our hy-
pothesis regarding the priority of the balanced-bilingual group
compared to the other two groups was partially confirmed. The
pattern of results obtained in the present study showed that the
English-dominant group outperformed the Hebrew-dominant
group with significant differences emerging only between the
Hebrew-dominant group and the balanced-bilingual group.
In this context, similarly to previously reported findings us-
ing task switching paradigms, bilingual subjects in the current
study did not exhibit significant differences in this domain. In
that regard, this result is similar to previous task switching
studies in which bilinguals had smaller switch costs but equi-
valent overall response times (Prior & Gollan, 2011; Prior &
MacWhinney, 2010), but contrasts with findings from conflict
resolution tasks, where overall speed advantages are robust
(Costa et al., 2009; see also, Hilchey & Klein, 2011). Note that
the balanced-bilingual group subjects as well as the subjects of
the Hebrew-dominant group have lived all of their lives in Is-
rael, excluding a few subjects from the balanced-bilingual
group who spent part of their lives in an English speaking
country. However, and interestingly, both in the Alternate Uses
Task which represents spontaneous cognitive flexibility and in
the Trails Task which represents reactive cognitive flexibility,
the balanced-bilinguals were found to be superior to the He-
brew-dominant group but not compared to those who mastered
English as their primary language.
Although the Hebrew-dominant group reported having more
second language proficiency than the English-dominant group,
it is possible that cultural proclivities led to over-estimation.
The language histories of both language-dominant groups dif-
fered from the distinctive pattern among the balanced-bilingual
Table 5.
Statistical comparisons (Mann-Whitney) between three groups.
Balanced bilinguals Hebrew dominant Balanced bilinguals English dominant Hebrew dominant English dominant
Z p Z p Z p
WCSTFC 0 0.5 −0.084 0.47 −0.063 0.48
WCSTTE −0.035 0.48 −0.29 0.4 −0.057 0.48
WCSTPR −1.1 0.14 −1.13 0.14 −0.14 0.45
Note: WCSTFC : Wisconsin card sort task first category; WCSTTE: Wisconsin card sort task total error; WCSTPR: Wisconsin card sort task perseverative responses.
Table 6.
Interactions between balanced-bilinguals and the Hebrew-dominant group and the Alternate Uses Task versus other experimental measures.
Z scores Z scores
Task
Balanced bilingualsHebrew-dominant
Task
Balanced bilingualsHebrew-dominant
F p
Trails 2 0.21 −0.50 0.7150.404
Tr2/Tr1 0.12 −0.12 3.21 0.08
WCSTFC 0.05 −0.02 5.08 0.03*
WCSTTE −0.02 −0.11 4.8 0.036*
WCSTPR 0.16 -0.24 1.91 0.176
WCST-composite 0.07 −0.12 4.5 0.04*
Alternate uses 0.51 −0.57
Desflcr −0.03 −0.15 9.4 0.004*

R. IBRAHIM ET AL.
group who had acquired both English and Hebrew in early
childhood and used both languages on a daily basis throughout
life. In addition, the pattern of results reported above reinforces
the assumption that the Hebrew-dominant group overestimated
it’s second language proficiency compared to the English-
dominant group, since the raw scores on most experimental
measures revealed better performance of the English-dominant
group. Nonetheless, future research should examine language
proficiency by directly evaluating language proficiency.
In the Alternate Uses Task, the slight difference between the
English-dominant and the Hebrew-dominant groups might be
explained by the fact that foreign students were previously
exposed in their natural environment to more possible uses of
objects from this task. Also, the English-dominant group out-
performed the Hebrew-dominant group in the second part of the
Trails task which necessitates switching between numbers and
letters. Most of the English letters in the Trails task contains
only one syllable in contrast to the Hebrew letters which are
mostly constructed of two syllables. This fact might be the
reason for faster memory retrieval of the English alphabet and
therefore for the superior performance of the English-dominant
group in this part of the task. Yet, in spite of the putative cul-
tural and linguistic advantages of the English-dominant subjects,
this group did not outperform the balanced-bilingual group,
suggesting genuine cognitive benefits of bilingualism.
The second hypothesis of this study predicted that the bal-
anced-bilingual group superiority should be greater in cognitive
tasks which represent spontaneous cognitive flexibility com-
pared to reactive cognitive flexibility tasks. Tasks which neces-
sitate spontaneous cognitive flexibility pose a greater cognitive
challenge because they require the formation of strategies for
searching information in memory and often require a bypassing
of automatic responses. Due to the fact that the research sub-
jects were primarily high-functioning individuals (students), we
hypothesized that the benefits of bilingualism would be more
pronounced in tasks which are more cognitively challenging.
However, the results of the present study, using two composite
measures of the experimental tasks, did not reveal an interac-
tion between group and type of cognitive flexibility. Nonethe-
less, comparing the two tasks where there was a significant dif-
ference between the balanced-bilingual group and the Hebrew-
dominant group, showed that the difference between the groups
showed twice as much variance in the Alternate Uses Task
which requires spontaneous cognitive flexibility than in the
Trails task which taps reactive cognitive flexibility.
These results demonstrate that the type of linguistic experi-
ence (balanced/dominant bilingualism) has more influence on a
task which necessitates spontaneous cognitive flexibility.
The Alternate Uses Task has the highest cognitive demands
among all research tasks. The performance of the balanced-
bilingual group compared to the Hebrew-dominant group was
significantly better in this task than in most experimental meas-
ures. This finding reinforces results of previous studies demon-
strating the cognitive benefits of bilingualism (Gilhooly et al.,
2007).
The Alternate Uses Task involves several executive proc-
esses. According to Gilhooly et al. (2007), initial responses in
this task are based on a strategy of retrieval from long term
memory of already known alternate uses associated with past
experience with the target objects. After the initial automatic
retrievals have been exhausted, more effortful and executively
loading strategies are used in order to find novel alternate uses.
Two main executive processes, which are involved in the use of
strategies, are inhibition and switching (Baddeley, 2003; Mi-
yake, Friedman, Emerson, Witzki, & Howerter, 2000). In the
Alternate Uses Task, the dominant use of the object must be
inhibited. In addition, the memory strategy requires inhibition
of earlier produced dominant memories as the process contin-
ues to produce responses. Furthermore, possible responses will
have to be evaluated for suitability and unsuitable ones inhib-
ited. A decision must be made as to when to switch from the
memory strategy to one of the other strategies. Further deci-
sions about switching from one attribute of an object to another
are also required in addition to inhibition of previously used
cues.
Gilhooly et al. (2007) found that subjects with greater execu-
tive capacity were better able to switch to more demanding
strategies and produce novel alternate uses which were not
based on personal past experience.
It is possible that life-long bilingual experience requiring
consistent switching between two languages along with inhibi-
tion of the irrelevant language depending on the situation, con-
tributed to the balanced-bilinguals advantage in this task which
is based on the executive functions of inhibition and switching.
The Alternate Uses Task is considered to be a divergent
thinking task (Guilford, Christensen, Merrifield & Wilson,
1978). According to Boden’s (2004: p. 2) terminology, diver-
gent production tasks involve “personal-psychological creativ-
ity”, i.e., producing an idea that is new to the person who pro-
duces it, irrespective of how many people have had the idea
before. In validation studies, divergent tests have been found to
be better correlated with real life measures of creative behavior,
such as gaining patents, producing novels and plays, founding
businesses or professional organizations (Plucker, 1999), than
with convergent tests of intelligence such as Raven’s Matrices.
Future research should examine the relationship between bilin-
gualism and creativity in adults using additional divergent
thinking tasks like the present Alternate Uses Task.
Previous studies among adults reporting a bilingual advan-
tage in tasks based on executive functions have used tasks
which are based on visuo-spatial perception such as the Simon
Task (Bialystok et al., 2004) or the Antisaccade Task (Bialy-
stok, Craik, & Ryan, 2006). However, in a few cases, the re-
sults have not been fully replicated when the Simon Task was
used (Bialystok, Martin, & Viswanathan, 2005). Furthermore, a
recent investigation found that daily experience in bilingualism
or massive musical training which engages executive control
can be generalized to other domains in which executive func-
tions are also required (Bialystok & DePape, 2009).
The greatest effect was found in tasks which are similar to
the type of activity involved in the experience. Therefore we
believe that this may reflect the different modality of the task.
The results of the present study, in which the balanced-bilingual
group's advantage in spontaneous cognitive flexibility tasks was
found in a linguistic task (Alternate Uses) and not in a task
which is based on spatial perception (Design Fluency), need
further research in order to elaborate the linguistic aspect and
explore the consistency of the bilingual advantage in linguistic
tasks which involve higher cognitive functions.
Conclusion and Future Research
In this study, we hypothesized that balanced bilingual sub-
jects would have superiority in the above tasks compared to
8

R. IBRAHIM ET AL.
dominant bilingual subjects. We hypothesized that the superior-
ity of the balanced bilinguals would be greater in cognitive
tasks which required spontaneous cognitive flexibility appar-
ently, due to the fact that spontaneous cognitive flexibility re-
quired more cognitive resources and more advanced executive
abilities than reactive cognitive flexibility. Results of the pre-
sent study demonstrated an advantage of bilingualism only
compared to individuals who share the same culture. No inter-
action was found between group and type of cognitive flexibil-
ity.
The present study has a limitation that the reader should take
into consideration. The background experiences of the three
groups were not the same, since the Hebrew-dominant group
grew up in Israel while English-dominant group were foreign
students studying in Israel. Therefore, it may well be that the
educational qualifications of these two groups differ. In order to
substantiate the findings of this study, it is therefore warranted
to conduct further research using bilinguals who have mastered
two closely related languages such as English and Spanish and
two dissimilar languages such as Chinese and Arabic. For the
Arabic speaking group, it is suggested that the study be repli-
cated with attention paid to the diglossic context existing for the
Arab readers. This should include more rigorous control re-
garding the familiarity of the items in both spoken and literary
Arabic as it has proved that the distance between the two forms
constitute a kind of bilingualisim and has an impact on lexical
representation (Ibrahim & Aharon-Peretz, 2005), cognitive
(Ibrahim, 2010) and metacognitive processess (Eviatar & Ibra-
him, 2001).
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